>> cue the siren tonight behind john schriffen in columbus circle. john, you've been a great sport for us. this has long been called black friday, of course, but the blk eyes, the bruises, the typical kay use has turned downright dangerous. how did we get to this point? abc's lindsey davis tonight inside this extreme shopper, this hunt for a steal. >> reporter: what looked a lot like survival of the fittest is really just the pursuit of that black friday deal. watch as the quest for pre-paid cell phones in georgia turned into a post-thanksgiving feeding frenzy. forget table manners. this walmart shopper literally chomping at the bit, appears to end up with someone's hand in her mouth. walmart says no one was injured. but this mob mentality is not surprising to those who have studied this frenzied black friday phenomenon. >> i think it is definitely the hunter/gatherer mentality. i'm going to go out and i'm going to hunt for the best deal. >> reporter: sipsychologists sa the stores with their doorbuster deals and limited time only creates an urgency?